[Amps] AL-811 & 572's
W7MJM
w7mjm at arrl.net
Wed Feb 9 15:40:18 PST 2011
"W8JI probably recommended using only 3 tubes in the 811H because it will
reduce filament power, which will reduce the load on the transformer. The
power is limited by the voltage and current of the power transformer and 4
tubes will not gain you anything."
Thanks for the explanation, Colin.
73,
Martin
W7MJM
----- Original Message -----
From: "k7fm" <k7fm at teleport.com>
To: "W7MJM" <w7mjm at arrl.net>
Sent: Wednesday, February 09, 2011 1:22 PM
Subject: Re: [Amps] AL-811 & 572's
> Hi Martin:
>
> The 572-B will not put out any more power than the 811A. It simply has
> more plate dissipation and will be more rugged. Also will withstand more
> plate voltage.
>
> I have only read about the 811 and the 811H - but would be surprised if
> they had the same power transformer. That would not make economic sense.
>
> W8JI probably recommended using only 3 tubes in the 811H because it will
> reduce filament power, which will reduce the load on the transformer. The
> power is limited by the voltage and current of the power transformer and 4
> tubes will not gain you anything.
>
> Replacement of the 4 x 811A tubes in the Collins 30L-1 with 4 x 572-B
> tubes will result in no increase in power output.
>
> 600 watts for your amp sounds right.
>
> 73, Colin K7FM
>
More information about the Amps
mailing list